Adjustable tuyere for metallurgical vessels

ABSTRACT

A refractory lined metallurgical vessel for converting molten ferrous metal to steel and having a removable refractory bottom insert provided with tuyeres for allowing injection of oxygen and other gases through the molten metal. The tuyeres extend through ball and socket joints in an insert bottom plate and voids in the refractory bottom which permit adjustment of the angle between the tuyeres and the vertical axis of the vessel. After the proper angle has been selected, the voids between the tuyeres and the bottom refractory lining are filled with refractory mortar. Such vessels may also include similarly adjustable tuyeres extending into the vessel side above the molten metal for directing oxygen or other gases onto the surface of the melt.

United States Patent [191 Fisher et a1.

[ Oct. 15, 1974 I ADJUSTABLE TUYERE FOR METALLURGICAL VESSELS [22] Filed: Aug. 18, 1972 [2]] Appl. No: 281,780

[56] References Cited UNITED STATES PATENTS 405,766 6/1889 Bookwalter 266/35 698,431 4/1902 Behrcnd 266/35 757,803 4/1904 Burron 266/35 1,941,545 l/l934 Eichenberg et a1. 266/31 X 3,706,549 12/1972 Knuppel et a1. 266/35 FOREIGN PATENTS OR APPLICATIONS 975,238 3/1951 France 287/88 Germany 266/35 Germany 266/41 Primary Examiner--Andrew R. Juhasz Assistant Examiner-W. R. Briggs Attorney, Agent, or Firm-Fred Wiviott; Ralph G. Hohenfeldt [57] ABSTRACT A refractory lined metallurgical vessel for converting molten ferrous metal to steel and having a removable refractory bottom insert provided with tuyeres for allowing injection of oxygen and other gases through the molten metal. The tuyeres extend through ball and socket joints in an insert bottom plate and voids in the refractory bottom which permit adjustment of the angle between the tuyeres and the vertical axis of the vessel. After the proper angle has been selected, the voids between the tuyeres and the bottom refractory lining are filled with refractory mortar. Such vessels may also include similarly adjustable tuyeres extending into the vessel side above the molten metal for directing oxygen or other gases onto the surface of the melt.

17 Claims, 4 Drawing Figures PAIENILUQU I 51914 SHEH 10F 3 FIG. I

PAIENIED an x 51974 sum ear 3 ADJUSTABLE TUYERE FOR METALLURGICAL VESSELS BACKGROUND OF THE INVENTION This invention relates to converter vessels and more particularly to converter vessels of the bottom blown type.

Bottom blown converter vessels have been developed for converting molten ferrous metal to steel by blowing oxygen through the molten metal by means of tuyeres located in the bottom of the vessel. Because the vessel bottoms tend to wear faster than the remaining vessel refractory, such vessels are often provided removable bottom inserts. These removable bottoms normally include tuyeres mounted on an insert bottom plate and extend upwardly through the refractory bottom structure. The tuyeres of bottom blown vessels may also comprise concentric pipes which permit the simultaneous injection of oxygen through the center pipe and a shielding gas through the space between the pipes.

In bottom blown converter vessels, it may be desirable to inject the gases through the bottom at an acute angle relative to the vertical axis of the vessel for the purpose of inducing a stirring action in the molten metal within the vessel. This facilitates mixing of the melt and slag, concentration equilibrium and shortening of the diffusion paths. Toward this end, the tuyeres may all be located on the same side of the vessel and inclined in opposite directions or they may be arranged in groups on the opposite sides of the vessel with the tuyeres in each group oriented oppositely. In some instances, the tuyeres may all be oriented at the same angle or at different angles depending upon their distance from the vertical axis of the vessel. In prior art vessels of this type, the tuyere pipes are rigidly attached to a bottom plate at a predetermined angle and the bottom refractory lining is formed therearound.

As those skilled in the art will appreciate, a typical installation may include a number of bottom blown converter vessels. Because the bottom refractory of such vessels is normally consumed at a faster rate than that of the remainder of the vessel, it becomes periodically necessary to change vessel bottoms. To prevent costly down time for such vessels, replacement bottom inserts are generally fabricated prior to the need for their replacement. Since different converter vessels may require tuyeres mounted at different angles, it was necessary to stock a great quantity of prior art bottoms having tuyeres fabricated at fixed angles. Further, because of the number of possible tuyere angles in the same vessels and in different vessels, it was necessary to stock large numbers of prior art tuyeres.

Additionally, it may be desirable to blow oxygen over the top of the molten metal to react with carbon mon oxide, hydrogen and other oxidizable gases which may evolve from the melt.

SUMMARY OF THE INVENTION It is the general object of the invention to provide a converter vessel refractory insert having tuyeres which may be angularly adjusted prior to installation.

It is a further object of the invention to provide a converter vessel bottom insert which may be adjustably adapted to suit various converter vessels.

Yet another object of the invention is to provide an angularly adjustable tuyere for converter vessels.

Another object of the invention is to provide a converter vessel with side tuyeres for delivering oxygen or other gases above the level of molten metal and which may be angularly adjustable prior to installation.

These and other objects and advantages of the present invention will become more apparent from the detailed description thereof taken with the accompanying drawings.

In general terms, the invention comprises a bottom blown converter vessel having a removable bottom insert provided with tuyeres mounted on angularly adjustable tuyere support means and :frusto-conical recesses formed in the bottom refractory tobe filled after the tuyeres have been adjusted to the desired angle. Similar adjustable tuyeres may be provided in the side of the vessel above for delivering gases above the surface of the molten metal.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front elevational view, partly in section, of a converter vessel having a tuyere system according to the present invention; and

FIG. 2 is an enlarged view of a tuyere according to the present invention with parts broken away.

FIG. 3 is a fragmentary view showing an alternate embodiment of the invention.

FIG. 4 is a cross-sectional view of an alternate embodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT A bottom blown converter vessel 10 is shown in FIG. 1 to include a metallic shell 11 and a refractory lining 12. As those skilled in the art will appreciate, converter vessels of the type illustrated are generally supported in a conventional manner on a trunnion ring 13 which has a trunnion pin 14 extending from each of its opposite sides. The trunnion pins 14 are suitably supported in a well known manner on bearing structures (not shown) and are coupled to a suitable drive mechanism (not shown) for tilting vessel 10 to each of a plurality of positions as may be required during a process cycle. A smoke hood 15 may be disposed above the open upper end of a vessel 10 when the latter is in its vertical position as shown in FIG. 1 to prevent the discharge of pollutants during operation of the vessel.

The vessel 10 has a removable: bottom portion 16 which may be attached to the vessel 10 in any suitable manner. In the illustrated embodiment, for example, bottom 16 may be provided with a flange 17 for being suitably attached by a plurality of bolts 18 to a mating flange 19 on vessel shell 10. The bottom 16 includes a plurality of tuyeres 21, refractory 20 and extending therethrough. The tuyeres 21 are suitably mounted by angular adjustment assembly 22 on a metallic plate 23 as will be described more fully below. The tuyeres 21 each includes a pair of concentric pipes. The inner pipe (not seen in FIG. 1) is connected to a source of oxygen containing gas through delivery pipe 24. The outer tuyere pipe 25 is connected to a suitable source of a shielding gas, such as propane, through delivery pipe 27. Normally oxygen will be blown into the molten metal in vessel 10 to oxidize carbon and other impurities while the shielding gas will be blown through outer tuyere pipe 25 to prolong the life of the refractory 20.

The individual tuyere assemblies 21 may have any convenient form for providing a sheath of shielding gas around an oxygen stream.

Referring now to FIG. 2, which shows an exemplary embodiment, the individual tuyere assembly 21 is shown to include an inner tuyere pipe 28 and an outer coaxial tuyere pipe 25 which is spaced from inner pipe 28. Inner pipe 28 may be connected to the oxygen pipe delivery 24 by a branch pipe 30 and an elbow connection 31. Outer tuyere pipe 25 may be coupled to delivery pipe 27 by a manifold pipe (not shown) through a coupling pipe 32, a coupling 33, pipe 34, and a union 35.

Inner tuyere pipe also passes through union 35 and has a reduced outer diameter which begins at the point of connection of outer tuyere pipe 25 with said union 35. Nuts 38 and 39 respectively secure the tuyere pipes 25 and 28 to the union 35 and to each other.

The angular adjustment assembly 22 secures the tuyeres 21 to the bottom plate 23 and permits angular adjustment thereof relative to the refractory 20. Adjustment assembly 22 includes a ball 42 having an axial bore 43 for receiving the tuyere 21 therethrough. The tuyere 21 may be releasably secured in the bore 43 of ball 42 in any suitable manner such as by a threaded clamp member 45 which may be secured to the outer tuyere pipe 25 and is received in mating threads formed in the outer end of bore 43. A plurality of openings 48 are formed in bottom plate 23 for receiving the tuyere 21 and each consists of a pair of oppositely directed frusto-conical surfaces 49 and 50. A ring clamp 52 is secured to base plate 20 around each opening 48 by bolts 54 and nuts 55 and each includes a spheroidal surface 57 which engages ball 42 for holding the same against surface 50. Bottom refractory 20 also has a plurality of frusto-conical openings 60 which register with and forms a continuation of the surface 49 formed on bottom plate 23.

The adjustment assembly 22 permits the tuyeres to be positioned at any angle and direction within the limits of the surfaces 49 and 60 as shown by phantom lines in FIG. 2. When a vessel bottom is to be installed, the tuyeres 21 are initially positioned at the desired angle relative to the bottom refractory 20. The ring clamp 52 associated with each tuyere is then tightened to secure the tuyere at the preset angle. The recesses in bottom 20 are then filled with a refractory mortar to fill the voids around tuyeres 21. Once installed, the tuyeres 21 will be replaced along with the bottom member 20 or the tuyeres 21 may be replaced individually by removing the elbow 31, the union 35 and the clamp member 45.

Normally the tuyeres 21 are mounted in the vessel at an angle of about l5 relative to the vertical, although this may vary from vessel to vessel. In addition, the angle of tuyere inclination may vary within a particular vessel on the basis of the distance that a particular tuyere may be from the vessel's vertical axis. Thus, because each of the tuyeres 21 are individually adjustable both as to angle and direction, the same tuyeres may be employed in a wide variety of vessel configurations.

FIG. 3 illustrates an alternate embodiment of the invention wherein the vessel 10 includes a plurality of side tuyeres 21' which extend through a frusto-conical opening 60' formed in the shell 11 and lining 12 and above the surface of the molten metal bath 70. While only a portion of vessel 10 is shown in FIG. 3, it will be understood that it includes the bottom tuyere 21 shown in FIG. 1. The tuyeres 21 are mounted by angular adjustment assembly 22' to shell 11 in any suitable manner such as by a support assembly 71 which is suitably affixed in a corresponding opening 72 in shell 11. A pair of delivery pipes 73 and 74 extend around the vessel and are suitably connected to supply tuyeres 21 with an oxygen containing gas and a shielding gas respectively.

While the tuyeres 21 and the adjustable support assembly 22 may be substantially identical to the tuyeres 21 and the support assembly 22, both assemblies may also take the alternate form shown in FIG. 4. Here the tuyere assembly 21' is shown to include an outer tuyere pipe and an inner concentric tuyere pipe 81. The adjustable support assembly 22 includes a ball 82 and a clamp assembly 83. The ball 82 has a pair of coaxial counter sunk bores 84a and 84b whose inner ends are spaced apart to form a shoulder 86. The outer tuyere pipe 80 is formed in two sections 80a and 8012 which are respectively secured in bores 84a and 84b in an abutting relation to shoulder 86. Those skilled in the art will appreciate that pipe sections 8011 and 80b may be secured in any suitable manner such as by welding. Suitable flanges 85 and 86 may be respectively secured to the outer tuyere pipe section 800 and inner tuyere pipe 81 for securing the same to each other and to a third flange 87 secured to pipe section 88 which couples the inner tuyere pipe 81 to air delivery pipe 73. Any suitable means, such as nuts 89 and bolts 90, which extend through aligned holes in flanges 85, 86 and 87 may be employed to secure said flanges.

The inside diameters of tuyere pipe sections 800 and 80b are smaller than the outside diameter of the concentrically arranged inner tuyere pipe 81 to provide a gap 91 therebetween for the delivery of shielding gas in a sheath around the oxygen to be provided through inner pipe 81.

An internally threaded nipple 92 may be secured to outer tuyere pipe section 80a and around an opening 94 therein for receiving the threaded end of a pipe 95 whose other end is connected to shielding gas delivery pipe 74. A suitable gasket 96 may be provided between flanges 85 and 86 to seal the outer end of gap 91.

Clamp assembly 83 is shown in FIG. 4 to include a short cylindrical section 98 which is secured at one end in opening 72 and which supports an annular flange 99 at its other end. Flange 99 has an inner, generally frusto-conical surface 100 for engaging one side of ball 82. A ring 102 is disposed in general parallelism with flange 99 and has the same general configuration as said flange including a frusto-conical surface 102 which engages the other side of ball 82. A suitable clamping means, such as nuts 103 and bolts 104 which extend between flange 99 and ring 101, clamp ball 82 firmly against flange 99. A gasket 105 may be provided between ball 82 and surface 100 to provide a seal around opening 72.

It will be appreciated that tuyere assembly 21' may initially be adjusted in any one of a number of possible angular positions relative to the refractory lining 12 after which it may be retained in this position by tightening bolts 104 and filling in the opening 60' in lining 12. A cap 106 may be threaded onto the inner end of tuyere pipe 80b to protect the end of tuyere 21' during assembly.

It will be appreciated that by mounting the tuyere 21' by means of the angular adjustment assemblies 22, the angle of inclination of tuyeres 21' relative to the surface of metal 70 may be varied in accordance with the size and shape of the vessel 10. Normally the angle of tuyeres 21 will be mounted at an angle of between 3 and l5 with respect to horizontal or with respect to the surface of the melt, however, a greater or lesser angle could be used. After the tuyeres 21' have been positioned at the desired angle and the adjustment assemblies 22 secured, the openings 60' are filled with a refractory mortar 65 For a more complete description of the purposes of the tuyere 21', reference is made to copending application Ser. No. 215,392 filed Jan. 4, 1972 and assigned to the assignee of the present invention.

While only a few embodiments of the invention have been illustrated and described, it is not intended to be limited thereby.

We claim:

1. A metallurgical vessel having a refractory lining and constructed and arranged for being tilted about a generally horizontal axis, said vessel having a second axis which is generally vertical when said vessel is in an untilted position,

at least one tuyere means,

the lower end of said vessel having an opening formed therein and extending through said refractory lining, at least the inner end of said opening being substantially larger than the cross sectional area of said tuyere means,

tuyere support means mounted on the lower end of said vessel and external of said refractory lining and adjacent said opening,

said tuyere means being mounted on said tuyere support means and extending through said opening and toward the interior of said vessel, said tuyere support means including a first portion mounted on said vessel and a second portion mounted on said tuyere, said portions being adjustably engageable relative to said vertical axis,

means for securing said first and second portions in each of a plurality of angular positions whereby said tuyere means may be mounted in said opening in any one of a plurality of angular positions relative to said vertical axis,

and refractory closing the remainder of said opening not occupied by said tuyere means to affix said tuyere means in its adjusted angular position and to seal said opening.

2. The invention set forth in claim 1 wherein one of said portions comprises a ball and the other of said portions comprises support means for said ball.

3. The invention set forth in claim 3 wherein said tuyere meansextends through said ball and is affixed thereto, said tuyere support means includes ball receiving means mounted on said vessel and clamp means releasably securable to said ball receiving means, one side of said ball engaging said ball receiving means and the other side of said ball being engaged by said clamp means for securing said ball in position.

4. The invention set forth in claim 3 wherein said ball receiving means and clamp means each having an annular opening formed therein and engageable by said ball, said openings each being smaller in diameter than said ball and being tapered in the direction of the curvature of said ball.

5. The invention set forth in claim 4 wherein said vessel has a metallic shell, an aperture formed in said metallic shell in registry with said opening, said ball receiving means including a tubular element secured to said shell in coaxial relation to said aperture, and plate means affixed on the outer end of said tubular element, said annular opening being formed in said plate means.

6. The invention set forth in claim 5 wherein at least one of said openings is frusto-conical.

7. The invention set forth in claim 1 and including a bottom plate removably secured to said vessel, a plurality of tuyeres, a plurality of said tuyere support means for the mounting of each said tuyeres on said bottom plate, a refractory bottom member secured to said bottom plate and having a plurality of openings extending therethrough one of said adjustable mounting means being disposed adjacent each of said openings, one of said tuyeres being secured to each of said mounting means and extending through a respective one of said openings, at least the inner endsof said openings being larger than the cross sectional area of said tuyeres to permit angular and directional adjustment thereof, and refractory means filling the remainder of said openings not occupied by said tuyere means to seal said openings and fix said tuyere means in position.

8. The invention set forth in claim 7 wherein one of I each of said portions comprises a ball and the other of each of said portions comprises support means for said ball.

9. The invention set forth in claim 8 wherein each of said tuyere means extends through said ball and is affixed thereto, each of said ball support means including ball receiving means mounted on said vessel and clamp means releasably securable to said ball receiving means, one side of each ball engaging its respective ball receiving means and the other side of each ball being engaged by its respective clamp means for securing each ball in position.

10. The combination set forth in claim 9 wherein each of said tuyeres includes a first internal pipe adapted to be connected to a source of an oxygen containing gas and a second pipe surrounding said first pipe and being spaced therefrom and adapted to be connected to a source of a shielding gas.

11. The combination set forth in claim 1 wherein said tuyere includes a first internal pipe adapted to be connected to a source of an oxygen containing gas and a second pipe surrounding said first pipe and being spaced therefrom and adapted to be connected to a source of a shielding gas.

12. The invention set forth in claim 1 and including at least one additional tuyere means, said vessel having the second opening formed in the side thereof and above the level of molten metal to be disposed in said vessel, at least the inner end of said second opening being substantially larger than the cross section area of said second tuyere means, at least one additional tuyere support means mounted on the side of said vessel, said additional tuyere means extending through said second opening and being supported therein by said additional tuyere support means, said additional tuyere support means having a first part engaging said additional tuyere and a second part mounted on said vessel, said first and second parts being adjustably engageable relative to said horizontal axis, and means for securing said first part to said second part and each of a plurality of angular positions relative to said horizontal axis to fix said additional tuyere means in one of a plurality of angular positions, and a refractory material filling said second opening and surrounding said additional tuyere means for fixing said additional tuyere means in its adjusted position and for sealing said opening.

13. The invention set forth in claim 12 wherein one of said parts comprises a ball and the other of each of said parts comprises support means for said ball.

14. The invention set forth in claim 12 wherein said first tuyere support part comprises a ball and said second tuyere support part includes support means for said ball, said additional tuyere extending through said ball and being affixed thereto, said ball support means including ball receiving means mounted on said vessel and having an aperture therein to permit the passage of said tuyere therethrough, said ball receiving means being engageable by one side of said ball, and clamp means releasably mounted on said ball receiving means and engageable with the other side of said ball.

15. The combination set forth in claim 14 wherein said additional tuyeres includes a first internal pipe adapted to be connected to a source of an oxygen containing gas and a second pipe surrounding said first pipe and being spaced therefrom and adapted to be connected to a source of a shielding gas.

16. The invention set forth in claim 14 wherein said vessel has a metallic shell, an aperture opening formed in said metallic shell in registry with each of said openings, each of said tuyere support means including a tubular element secured to said shell in coaxial relation to its respective aperture and plate means affixed on the outer end of each tubular element, each of said plate means having an annular ball receiving surface formed therein and defining an opening in said plate means, said surface having a small diameter end adjacent said tubular element and a large diameter end on the opposite side thereof, each of said diameters being smaller than the diameter of said ball means, each of said tube support means also including clamp means having an annular ball engaging surface defining a second opening for engaging the other side of its respective ball, said surface having a larger diameter end on the side thereof closest to said vessel and a small diameter on the opposite side thereof, the diameters of said second surfaces being smaller than that of their respective ball.

17. For use with a metallurgical vessel tiltable about a horizontal axis and having a refractory lining and a tuyere receiving opening extending through said refractory lining, said opening being larger at the inner end of said lining, the combination of, a tuyere for being received in said opening, said tuyere including a first internal pipe adapted to be connected to a source of an oxygen containing gas, a second pipe, means for securing said second pipe in a surrounding relation relative to said first pipe, the cross-sectional area of said second pipe being less than that of said opening, said second pipe being adapted to be connected to a source of a shielding gas, ball means having a bore formed therethrough for receiving said second pipe, said second pipe means being affixed in bore, and securing means for releasably securing said ball means to said metallurgical vessel with said tuyere means extending through said opening, including a tubular element adapted to be affixed at one end to said vessel, plate means affixed to the other end of said tubular element and having a first annular ball receiving opening formed therein, and clamp means releasably securable to said plate means and having a second annular ball receiving opening formed therein, said ball receiving surfaces engaging the opposite sides of said ball and each having a small diameter end and a larger diameter end to provide generally tapered surfaces facing inwardly toward said ball means and being generally inclined in the direction of ball curvature, said securing means being adapted to clamp said tuyere at a desired angle relative to said vessel so that said tuyere will be held in a desired orientation to permit that portion of said opening unoccupied by said tuyere to be filled with refractory material.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 5, 17 october 15, 1974 Inventor(s) Howard M. Fisher et al.

It is certified that error appears in the above-identified patent and that said Letters Patent'are hereby corrected as shown below:

Column 1, line 5h, Claim 3, cancel "3" and substitute Column 8, line 30, after "receiving" cancel "surfaces" and substitute openings Column 8, line 52, cancel "larger" and substitute large Signed and sealed this 22nd day of April 1975.

(SEAL) Attest:

. C. MARSHALL DANN RUTH C. MASON Commissioner of Patents Attesting Officer and Trademarks F ORM P0-\ 050 (10-69) 

1. A metallurgical vessel having a refractory lining and constrUcted and arranged for being tilted about a generally horizontal axis, said vessel having a second axis which is generally vertical when said vessel is in an untilted position, at least one tuyere means, the lower end of said vessel having an opening formed therein and extending through said refractory lining, at least the inner end of said opening being substantially larger than the cross sectional area of said tuyere means, tuyere support means mounted on the lower end of said vessel and external of said refractory lining and adjacent said opening, said tuyere means being mounted on said tuyere support means and extending through said opening and toward the interior of said vessel, said tuyere support means including a first portion mounted on said vessel and a second portion mounted on said tuyere, said portions being adjustably engageable relative to said vertical axis, means for securing said first and second portions in each of a plurality of angular positions whereby said tuyere means may be mounted in said opening in any one of a plurality of angular positions relative to said vertical axis, and refractory closing the remainder of said opening not occupied by said tuyere means to affix said tuyere means in its adjusted angular position and to seal said opening.
 2. The invention set forth in claim 1 wherein one of said portions comprises a ball and the other of said portions comprises support means for said ball.
 3. The invention set forth in claim 3 wherein said tuyere means extends through said ball and is affixed thereto, said tuyere support means includes ball receiving means mounted on said vessel and clamp means releasably securable to said ball receiving means, one side of said ball engaging said ball receiving means and the other side of said ball being engaged by said clamp means for securing said ball in position.
 4. The invention set forth in claim 3 wherein said ball receiving means and clamp means each having an annular opening formed therein and engageable by said ball, said openings each being smaller in diameter than said ball and being tapered in the direction of the curvature of said ball.
 5. The invention set forth in claim 4 wherein said vessel has a metallic shell, an aperture formed in said metallic shell in registry with said opening, said ball receiving means including a tubular element secured to said shell in coaxial relation to said aperture, and plate means affixed on the outer end of said tubular element, said annular opening being formed in said plate means.
 6. The invention set forth in claim 5 wherein at least one of said openings is frusto-conical.
 7. The invention set forth in claim 1 and including a bottom plate removably secured to said vessel, a plurality of tuyeres, a plurality of said tuyere support means for the mounting of each said tuyeres on said bottom plate, a refractory bottom member secured to said bottom plate and having a plurality of openings extending therethrough one of said adjustable mounting means being disposed adjacent each of said openings, one of said tuyeres being secured to each of said mounting means and extending through a respective one of said openings, at least the inner ends of said openings being larger than the cross sectional area of said tuyeres to permit angular and directional adjustment thereof, and refractory means filling the remainder of said openings not occupied by said tuyere means to seal said openings and fix said tuyere means in position.
 8. The invention set forth in claim 7 wherein one of each of said portions comprises a ball and the other of each of said portions comprises support means for said ball.
 9. The invention set forth in claim 8 wherein each of said tuyere means extends through said ball and is affixed thereto, each of said ball support means including ball receiving means mounted on said vessel and clamp means releasably securable to said ball receiving means, one side of each ball engaging its respective bAll receiving means and the other side of each ball being engaged by its respective clamp means for securing each ball in position.
 10. The combination set forth in claim 9 wherein each of said tuyeres includes a first internal pipe adapted to be connected to a source of an oxygen containing gas and a second pipe surrounding said first pipe and being spaced therefrom and adapted to be connected to a source of a shielding gas.
 11. The combination set forth in claim 1 wherein said tuyere includes a first internal pipe adapted to be connected to a source of an oxygen containing gas and a second pipe surrounding said first pipe and being spaced therefrom and adapted to be connected to a source of a shielding gas.
 12. The invention set forth in claim 1 and including at least one additional tuyere means, said vessel having the second opening formed in the side thereof and above the level of molten metal to be disposed in said vessel, at least the inner end of said second opening being substantially larger than the cross section area of said second tuyere means, at least one additional tuyere support means mounted on the side of said vessel, said additional tuyere means extending through said second opening and being supported therein by said additional tuyere support means, said additional tuyere support means having a first part engaging said additional tuyere and a second part mounted on said vessel, said first and second parts being adjustably engageable relative to said horizontal axis, and means for securing said first part to said second part and each of a plurality of angular positions relative to said horizontal axis to fix said additional tuyere means in one of a plurality of angular positions, and a refractory material filling said second opening and surrounding said additional tuyere means for fixing said additional tuyere means in its adjusted position and for sealing said opening.
 13. The invention set forth in claim 12 wherein one of said parts comprises a ball and the other of each of said parts comprises support means for said ball.
 14. The invention set forth in claim 12 wherein said first tuyere support part comprises a ball and said second tuyere support part includes support means for said ball, said additional tuyere extending through said ball and being affixed thereto, said ball support means including ball receiving means mounted on said vessel and having an aperture therein to permit the passage of said tuyere therethrough, said ball receiving means being engageable by one side of said ball, and clamp means releasably mounted on said ball receiving means and engageable with the other side of said ball.
 15. The combination set forth in claim 14 wherein said additional tuyeres includes a first internal pipe adapted to be connected to a source of an oxygen containing gas and a second pipe surrounding said first pipe and being spaced therefrom and adapted to be connected to a source of a shielding gas.
 16. The invention set forth in claim 14 wherein said vessel has a metallic shell, an aperture opening formed in said metallic shell in registry with each of said openings, each of said tuyere support means including a tubular element secured to said shell in coaxial relation to its respective aperture and plate means affixed on the outer end of each tubular element, each of said plate means having an annular ball receiving surface formed therein and defining an opening in said plate means, said surface having a small diameter end adjacent said tubular element and a large diameter end on the opposite side thereof, each of said diameters being smaller than the diameter of said ball means, each of said tube support means also including clamp means having an annular ball engaging surface defining a second opening for engaging the other side of its respective ball, said surface having a larger diameter end on the side thereof closest to said vessel and a small diameter on the opposite side thereof, the diameters of said second surfaCes being smaller than that of their respective ball.
 17. For use with a metallurgical vessel tiltable about a horizontal axis and having a refractory lining and a tuyere receiving opening extending through said refractory lining, said opening being larger at the inner end of said lining, the combination of, a tuyere for being received in said opening, said tuyere including a first internal pipe adapted to be connected to a source of an oxygen containing gas, a second pipe, means for securing said second pipe in a surrounding relation relative to said first pipe, the cross-sectional area of said second pipe being less than that of said opening, said second pipe being adapted to be connected to a source of a shielding gas, ball means having a bore formed therethrough for receiving said second pipe, said second pipe means being affixed in bore, and securing means for releasably securing said ball means to said metallurgical vessel with said tuyere means extending through said opening, including a tubular element adapted to be affixed at one end to said vessel, plate means affixed to the other end of said tubular element and having a first annular ball receiving opening formed therein, and clamp means releasably securable to said plate means and having a second annular ball receiving opening formed therein, said ball receiving surfaces engaging the opposite sides of said ball and each having a small diameter end and a larger diameter end to provide generally tapered surfaces facing inwardly toward said ball means and being generally inclined in the direction of ball curvature, said securing means being adapted to clamp said tuyere at a desired angle relative to said vessel so that said tuyere will be held in a desired orientation to permit that portion of said opening unoccupied by said tuyere to be filled with refractory material. 